Modular floor mat

ABSTRACT

A modular floor mat unit which can be used individually or in combination with adjoining floor mat modules to provide an elevated surface which insulates personnel or materials from the floor surface. The floor mat is a unitary structure comprised of a tread surface integrally attached to the top edges of interconnected flanges which form a support frame. A plurality of drainage openings in the tread surface allow liquids and other substances to be removed from the tread surface to the underlying floor and also ventilate the area beneath the mat. Unitary traction plugs fabricated from a flexible resilient material protrude above and below the floor mat to provide traction and prevent slippage. A plurality of finger elements having inclined top surfaces and detent interlock devices protrude from all sides of the floor mat to provide both an inclined threshold surrounding the mat and means for interlocking adjacent mat modules to form a larger mat area.

United States Patent [191 Ettlinger, Jr. et al.

[ MODULAR FLooR MAT [75] Inventors: Ralph Ettlinger, Jn, Glencoe; Glenn L. Beall, Gurnee, both of I11.

[73] Assignee: Economics Laboratory, Inc., St.

Paul, Minn.

[22] Filed: Dec. 12, 1974 [21] Appl. No.: 531,868

[ Get. 7, 1975 [57] ABSTRACT A modular floor mat unit which can be used individually or in combination with adjoining floor mat modules to provide an elevated surface which insulates personnel or materials from the floor surface. The floor mat is a unitary structure comprised of a tread surface integrally attached to the top edges of interconnected flanges which form a support frame. A plurality of drainage openings in the tread surface allow liquids and other substances to be removed from the tread surface to the underlying floor and also ventilate the area beneath the mat. Unitary traction plugs fabricated from a flexible resilient material protrude above and below the floor mat to provide traction and prevent slippage. A plurality of finger elements having inclined top surfaces and detent interlock devices protrude from all sides of the floor mat to provide both an inclined threshold surrounding the mat and means for interlocking adjacent mat modules to form a larger mat area.

9 Claims, 6 Drawing Figures Sheet 1of 2 3,909,996

LILJEIU DEIDEJ FIG. 2 59.5737

Z6 v 23 2! 3 4 20a z 2/ 20 22 5 umlill l a, 7 2 6 a 44- Will US. Patent Oct. 7,1975 Sheet 2 of 2 3,999,996

F E 2115 32 w .37 R

i zpaf B MODULAR FLOOR MAT BACKGROUND OF THE INVENTION 1. Field of the Invention Interlocking floor mat modules having an elevated tread surface and traction means to prevent slippage.

2. Description of the Prior Art Various types of floor mats have long been used to provide an elevated surface upon which to store goods or support work personnel. The construction of such mats generally provides a more comfortable walking surface, sllows liquids and other substances to drain be neath the matting and away from the feet of the workers and insulates the workers from heat and cold encountered in the floor area.

Many of the earlier floor mats were fabricated from individual ribs of rubber or similar materials. Such ribs were commonly held together by wires or other fasteners. As a result, these mats were inherently expensive because of the numerous assembly steps which had to be performed in their construction. In addition, many of these mat designs were not modular and were usable only as unitary mats. In those instances where the mats were of a modular design and could be used in groups, means were often not provided for interlocking adjoining mats or were deficient in that they were relatively complex devices incorporating sharp protruding elements, and were relatively difficult to disconnect con veniently.

Many of the presently available mat designs are intended to be used in partially enclosed areas such as in hallways or between cabinets or applicances where their edges would abut a baseboard surface. Such mats generally have abrupt edges which present a safety hazard if such mats are used in open areas where a worker could catch his foot or heel on the raised edge of the mat. Because these mats are intended to be usedin enclosed areas where the mat would be confined by the surrounding baseboard, means are often not provided for preventing slippage between the mat and the floor surface. When means are provided in a mat design for increasing the traction between the mat and the floor surface, they often incorporate devices which are not integral with the mat and which may easily become detached from the mat. The use of such devices may increase the complexity of the mat and result in a gener ally more expensive floor mat unit.

SUMMARY A modular floor mat unit which can'be used individually or in combination with other adjoining floor mat modules to provide an elevated support surface for storing goods or insulating personnel from the floor surface. A unitary support frame comprised of a plurality of longitudinal and transverse support flanges is utilizied to support a tread surface above the floor surface. The tread surface contains a plurality of openings for the drainage or water and other substances through the floor mat to prevent their accumulation on the tread surface.

A plurality of finger elements extends outwardly from all sides of the support frame to provide means for interlocking the floor mat unit with adjacent floor mat units to create a mat-which covers an extended area. The finger elements are spaced apart to allow them to be interlaced with the finger elements of an adjacent mat unit and have an inclined top surface which provides an inclined threshold completely around the mat to reduce the likelihood of tripping.

Locking means utilizing a pair of indexed protrusions and detents located on the side surface of every finger element are utilized to interlock the adjoining floor mats. The use of these interlock devices reduces the cost of production of the mat and provides a positive interlock which can be conveniently disconnected when desired.

Simple unitary traction plugs extend through the support frame and protrude both above the tread surface and below the bottom surface of the support frame. The traction plugs are made of a resilient flexible material and the protruding portions provide added traction between the tread surface and the personnel walking on the floor mat and between the bottom of the support frame and the floor surface. The plugs are press-fitted into a plurality of holes in the floor mat to provide an integrally attached traction device which is secure, provides traction on both surfaces of the mat unit, and is economical to produce. The floor mat is designed so that it can be produced in one piece by molding or otherwise to reduce the cost and eliminate complex assem bly steps.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view showing a group of interlocked floor mat modules;

FIG. 2 is a top plan view of a modular floor mat;

FIG. 3 is a bottom plan view of a modular floor mat;

FIG. 4 is a detailed cross-sectional view of the modular floor mat shown in FIG. 2 taken along the line 44;

FIG. 5 is a detailed cross-sectional view of the floor mat shown in FIG. 2 taken along the line 55; and

FIG. 6 is a detailed top plan view of the traction ridges surrounding the drainage openings shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1-6, wherein like numerals refer to like structural elements, modular floor mat 1 comprises a unitary support frame 2 which supports a tread surface 3 above a floor surface (not shown). A plurality of finger elements, each designated by the numeral 5, extend outwardly from each side of the support frame 2 and provide means by which identical adjacent mat modules, each designated by the numeral I00, can be joined together with floor mat 1 to form a larger mat surface as is shown in FIG. 1.

Referring to the bottom plan view of the floor mat 1 shown in FIG. 3, unitary support frame 2 comprises a plurality of longitudinal support flanges, each designated by the numeral 9, in combination with a plurality of transverse support flanges, each designated by the numeral 10. Longitudinal support flanges 9 each comprise a generally flat, thin upright member which is positioned in parallel spaced apart arrangement with similar longitudinal support flanges. Similarly, each of transverse support flanges 10 is a flat, thin upright member positioned generally perpendicular to the longitudinal support flanges 9 in parallel spaced apart arrangement. The periphery of the support frame 2 is comprised of outermost transverse support flanges 10a and longitudinal support flanges 9a. In the preferred embodiment, the floor mat module I has a generally square planform with each of the longitudinal support flanges 9-9:: and transverse support flanges l10a having essentially identical lengths. Where the various transverse and longitudinal support flanges intersect, they are integrally joined to one another such as would occur if the support frame were a molded unit. The Ap plicant has found that this particular design of a support frame 2 provides a firrn base for the tread surface 3 and a mat module which can be positioned in numerous floor spaces, either individually or in groupings. In addition, this particular design for support frame 2 allows the floor mat 1 to be easily manufactured as an integral unit. The preferred embodiment is manufactured from a thermoplastic material such as polyethylene to provide a floor mat which has firm support. yet which tends to cushion footsteps and which can withstand temperature extremes.

At various locations in the support frame 2, pedestal elements, each designated by the numeral 11, are attached to the support frame. As will be described in detail later, pedestal elements 11 serve as means for attaching traction plugs to the floor mat 1. In the preferred embodiment shown in the Figures, pedestal elements 11 are located at certain of the intersections be tween the longitudinal and transverse support flanges (9 and 10). These particular locations are utilized because the intersection points between the support flanges are the most resistant to compressive loads experienced by the floor mat 1. As is shown in FIGS. 3 and 4, pedestal elements 11 are generally cylindrical and extend from near the bottom edge of the support flange to the top edge where the support flange is integrally attached to the tread surface 3. A cylindrical opening 34 extends vertically through the center of each of the pedestal elements 11 for receiving the traction plug which will be described in detail later.

Tread surface 3 is a broad, relatively thin panel which extends across the top surface of support frame 2 and is generally coplanar with the top surfaces of finger elements 5. As is shown in detail in FIG. 4, tread surface 3 is integrally attached to the top edges of each of the longitudinal support flanges 9-9a and transverse support flanges 10-10a. Tread surface 3 is intended as a means for supporting goods or personnel positioned on the top of the floor mat 1. In the preferred embodiment, the tread surface 3 contains a plurality of square drainage openings 4 arranged in a checkerboard pattern which divides tread surface 3 into a plurality of longitudinal and transverse web members. The longitudinal web members are each denoted by the numeral 12 and are positioned in parallel spaced apart relationship with one another. The transverse web members are each denoted by the numeral 13 and are arranged in parallel spaced apart relationship, perpendicular to the longitudinal web members 12. In the preferred embodiment, each of longitudinal web members 12 is positioned coincident with a longitudinal support flange 9 extending below it generally along its centerline. Similarly, each of transverse web members 13 is positioned above a transverse support flange 10 which extends generally along its centerline. This particular interrelationship between the support flanges and web members provides a solid support for the tread surface 3 on support frame 2.

The utilization of a plurality of square drainage openings 4 allows liquids and other substances to be removed from the tread surface 3 to the floor area beneath the mat 1. This drainage of materials allows the tread surface 3 to be kept clean to reduce the likelihood of slippage between the feet of work personnel and the mat 1 due to accumulation of liquids or other substances. In addition, the drainage openings 4 ventilate the area beneath the floor mat 1 to allow evaporation of liquids from beneath the floor mat 1. To provide additional drainage of tread surface 3, a plurality of drainage channels are provided in the tread surface and communicate with drainage openings 4. As is shown in detail in FIG. 2, a plurality of longitudinal drainage ridges, each designated by the numeral 15 and positioned in spaced apart parallel relationship, extend across the tread surface 3 generally along the centerlines of the longitudinal web members 12. These longitudinal ridges l5 interconnect with a plurality of parallel spaced apart transverse ridges 16, each of which extends generally along the centerline of a transverse web member 13. A series of diagonal channels, each designated by the numeral 14, extends from the intersection of the longitudinal and transverse ridges into the drainage openings 4. Each of these channels is a shallow trough cut into the top surface of tread surface 3 and form an interconnecting network which allows liquids to be drained away from the entire area of tread surface 3 into the drainage openings 4. In addition, the presence of ridges 14-16 provides a texture to tread surface 3 which also increases the traction of the tread surface.

To provide traction to the top of tread surface 3 and the bottom of support frame 2, pliable resilient traction plugs, each designated by the numeral 6, are utilized and will be described in detail later. In addition, a plurality of corrugations 18 made up of a series of ridges 18a and alternating grooves 18b surround each of the drainage openings 4 to increase traction on the top of tread surface 3. Corrugations 18 are shown in detail in FIG. 6 and consist of a series of interspaced V-shaped ridges 18a and grooves 18b extending outwardly from each of the drainage openings. Corrugations 18 are relatively shallow and do not extend through the entire thickness of tread surface 3. In addition to providing traction to the tread surface 3, corrugations 18 provide additional drainage of liquids from the tread surface 3 into the drainage openings 4.

To provide means for interlocking floor mat l with adjacent identical floor mat modules to form a larger mat area, a plurality of finger elements 5 extend outwardly from each side of support frame 2. A grouping of floor mat modules is shown in FIG. 1. Referring to FIGS. 2-5, finger elements 5 are positioned in spaced apart relationship around the periphery of support frame 2. In addition to the finger elements 5, each of which is identical, a dual finger element 38 is located at one corner of the floor mat 1 and a square finger element 8 is located at a second corner of floor mat 1 epposite the dual finger element 38.

Each of finger elements 5 extend outwardly from the edge of support frame 2 and has a top surface comprised of a generally horizontal portion 21 coplanar with the top of tread surface 3 and an inclined portion 20 which slopes downwardly and outwardly from the support frame 2. The inclined'surfaces of finger elements 5 provide an inclined threshold spaced intermittently around the perimeter of floor mat 1 to reduce the likelihood of tripping on the floor mat edge. Traction ridges or serrations 202 are provided on the ramp surfaces (e.g. 20, 46, 47) of the finger elements to reduce the likelihood of slipping on the mat threshold. A vertical front surface 22 extends from the bottom edge of inclined surface portion toward the floor surface. The height of front surface 22 is relatively small to eliminate the presence of an abrupt edge on the floor mat. Opposed side surfaces 23 and 24 are attached to the top surface of finger elements 5 and have a bottom edge which is coplanar with the bottom edge of support flanges 9 and 10. Side surfaces 23 and 24 extend outwardly from support frame 2 at slightly oblique angles such that the side surfaces 23 and 24 slant toward one another to provide a trapezoidal planform to each of the finger elements 5. The various side and front elements of finger element 5 enclose the finger element and support its inclined surface so that it can support the weight of a person walking upon the floor mat 1.

Dual finger element 38 is located at one corner of floor mat l and has a shape different from finger ele ments 5. In particular, dual finger element 38 is comprised of vertical side surfaces 39 and 44 which extend outwardly from the sides of support ffame 2. Positioned opposite side surfaces 39 and 44 are side surfaces 41 and 42, respectively. Front surface 40 extends between side surfaces 39 and 41 and front surface 43 extends between side surfaces 42 and 44. The top surface of dual finger element 38 consists of a generally horizontal top surface 45 and separate incline surface portions 46 and 47 which slope outwardly and downwardly toward front surfaces 40 and 43, respectively. These various surfaces provide a V-shaped planform to element 38 which is intended to intermesh with the square finger element 108 of an adjoining floor mat module 100.

Located on the corner of floor mat module 1 opposite the dual finger element 38 is square finger element 8. As is shown in FIG. 3, square finger element 8 consists of generally vertical side surfaces 48 and 51 which extend outwardly from the sides of support frame 2. Front surfaces 49 and 50 adjoin side elements 48vand 51 respectively. The top surface of square finger ele ment 8 comprises a generally horizontal top portion 54 which intersects inclined top portions 52 and 53, each sloping downwardly and outwardly toward frontsurfaces 49 and 50, respectively.

Interspaced between finger elements 5, 8 and 38 are spacing elements, each designated by the numeral 27. Each spacing element 27 has an inclined top surface 28 which adjoins the side surfaces of finger elements 5, 8, and 38 and slopes downwardly to a front surface 28a. Two corner spacing elements, each designated by the numeral 37, extend outwardly from support frame 2 at opposite corners of floor mat 1. Each of elements 37 has a pair of inclined top surfaces 59 and 60 which slope outwardly and downwardly from the tread surface 3 and adjoin vertical front surfaces 57 and 58, respectively. Each of spacing elements 27 and 37 extend outwardly approximately one-half the length of the adjoining finger element to abut the finger elements of adjoining floor mats which are interlocked with floor mat As is shown in FIGS. 2 and 3, the various finger elements and spacing elements of floor mat 1 are arranged to form an open area between adjacent finger elements. The open areas are sized so as to accommodate the portions of finger elements which protrude beyond the spacing elements of an adjoining floor mat module 100. FIG. 1 shows the interlocking of several mats l and 100. This interlocking provides a generally continuous mat surface which nearly completely covers the enclosed floor surface. As is shown in FIG. ll, adjacent floor mat modules 1 and are positioned adjacent one another with the lower right hand corner of floor mat 1, having the dual finger element 38, abutting the lower left hand corner of floor mat module 100 which contains corner spacing elements 37. This arrangement of adjoining floor mats allows all of the mats to interlock with one another while providing a generally continuous and homogenous surface across the entire grouping of mats.

To provide means for forcibly interlocking the adjoining floor mat modules (eg 1 and 100), a series of interlock elements 26 and interlock detents 25 are provided on each of the side surfaces 24 and 23, respectively of finger elements 5. Similar interlock elements and interlock detents are provided on the side surfaces 39 and 44 of dual finger element 38 and side surfaces 48 and 51 of square finger element 8. In the preferred embodiment, interlock element 26 is a spherical segment which protrudes from the finger side surface and is positioned between the front surfaces of the finger element and the adjoining spacing element approxi mately midway up the finger side surface. The interlock detent 25 has a rounded concave surface which receives the interlock element 26 within it and is in indexed relationship with the interlock element so they meet when the fingers are intermeshed into locking position.

As is shown is detail in FIGS. 1 and 5, when one finger element 5 of floor mat I is positioned between adjacent finger elements of a second, adjoining floor mat 100, the interlock element 25 of one of the finger elements is indexed with the interlock detent of the adjoining finger element. Consequently, when the adjoining floor mats I and 100 are pressed together, the interlock element 26 is forced into the interlock detent 25. To aid in this interlocking process, in the preferred embodiment the side surfaces of the various finger ele ments are somewhat flexible and resilient and will yield slightly to allow the interlock element 26 to slide into the interlock detent 25. By providing interlock detents and elements on each of the various types of finger elements, a positive interlock between any number of adjoining floor mat modules (e.g. l and 100) is achieved. Interlock detent 25 and interlock element 26 firmly hold adjoining floor mat modules together while the resilient nature of the material from which the finger elements are manufactured allows the adjoining mats to be conveniently interlocked and disengaged by simple hand force.

To provide traction for the tread surface 3 to reduce the likelihood that a person walking on the floor would slip, and to also provide traction between the floor mat l and the floor surface upon which it rests, the present invention utilizes a plurality of traction plugs, each designated by the numeral 6. Referring to FIGS. 25, traction plugs 6 are positioned at various locations and protrude above the tread surface 3 and the top surfaces of several of the finger elements. While various patterns for the positioning of traction. plugs 6 on the floor mat module 1 may be utilized, the Applicant has found that it is particularly desirable to position the traction plugs 6 such that the average sized shoe of a person using the floor mats would always be in contact with at least one of the traction plugs 6 to provide traction between the tread surface 3 and the bottom surface of the persons shoe (not shown).

Referring to FIG. 4, each of the traction plugs 6 is generally cylindrical and consists of a central portion 31, a top portion 32 and a base portion 30. Traction plug 6 has a length greater than the distance between the top of tread surface 3 and the bottom of the support flanges 9 and 10. As a result, when the traction plug 6 is attached to the support frame 2, top portion 32 extends above the tread surface 3 and base portion 30 extends below the bottom of the support frame 2. The protruding top portion 32 provides an uneven surface to tread surface 3 which results in an increased traction and also provides a resilient material which tends to grip the rubber or leather sole of a persons shoe. Similarly, because the base portion 30 of traction plug 6 extends below the bottom of support frame 2, the entire floor mat l rests upon the protruding base portion 30 of the traction plug 6. Thus, when weight is applied to floor mat l, the plug base portion 30 is compressed as the support frame 2 is forced into abutting engagement with the floor surface. The resilient rubberlike material of the plug base portion 30 firmly abuts the floor upon which the mat is lying to provide traction between the floor mat 1 and the floor surface.

To provide a unitary traction plug design which al lows it to protrude above the tread surface 3 and below support frame 2, and to firmly attach the traction plug 6 to the floor mat 1, each of traction plugs 6 is attached to the floor mat by means of a cylindrical opening 34 in the pedestal elements 11 which were described earlier. In the preferred embodiment shown in FIG. 4, the top portion 32 and central portion 31 of traction plug 6 generally have the same diameter and this diameter is larger than the diameter of the opening 34. The base portion 30 has a larger diameter than central portion 31 and top portion 32. In addition, a central bore 33 extends from the base portion 30 to near the top portion 32 of each of the traction plugs 6. This design for traction plug 6 allows it to be press fitted into opening 34 in pedestal element 11. Because the base portion 30 is larger than the other portions of the traction plug 6, the traction plug 6 will bottomout on the bottom edge of pedestal element 11 when the plug is inserted into opening 34. Because the diameter of central portion 31 is larger than the inside diameter of opening 34, the plug 6 will tend to expand in the opening 34 to provide a firm fit between the traction plug 6 and the opening 34. In the event that the traction plugs become worn down from continued use, they can be replaced by removing them from the opening 34 and replacing them with new traction plugs.

The Applicant has found that a material known by the tradename of Kraton manufactured by the Shell Oil Company is particularly suitable for the traction plugs 6. This material is more elastomeric than many other materials and provides good traction properties. Other suitable materials for tractions plugs 6 may also be utilized where appropriate.

What is claimed is:

l. A unitary modular floor mat which can be used individually or in combination with other adjoining mat modules to cover a floor surface, comprising:

a. a unitary support frame comprised of a plurality of interconnected and spaced apart support flanges, at least some of said support flanges having coplanar top and bottom edges;

b. a tread surface supported above the floor surface by said support frame, said tread surface having top and bottom surfaces, said bottom surface integrally attached to the top edges of said support flanges;

c. said tread surface containing a plurality of drainage openings for draining substances off of the tread surface onto the underlying floor surface and ventilating the floor surface;

d. a plurality of finger elements protruding outwardly from each side of said support frame to intermesh with finger elements on an adjoining mat module, each of said finger elements having at least two side surfaces which support a top surface, a first portion of said top surface being integral and coplanar with said tread top surface and a second portion being an inclined surface which slopes outwardly and downwardly away from said tread surface toward the floor surface to form an inclined threshold sur rounding the mat periphery to prevent tripping;

e. each of said finger elements being spaced apart a sufficient distance so as to receive between adjacent finger elements a finger element from an ad joining floor mat module to create a generally continuous tread surface from interlocked mat modules;

f. interlock means attached to each of said finger element side surfaces to forcibly engage the finger element of an adjoining mat module which is positioned between adjacent finger elements, thereby interlocking adjacent floor mat modules;

g. a plurality of unitary traction plugs for providing traction to the tread surface and the bottom sur face of said support frame, each of said traction plugs having a flexible resilient top portion protruding above the tread surface and a flexible resilient base portion protruding below the bottom edge of said support flanges to abut the floor surface; and

h. attachment means for attaching said traction plugs to said floor mat with the plug top portion protruding above said tread surface and the plug base portion protruding below the bottom edge of said support flanges.

2. The modular floor mat of claim 1 wherein:

a. some of said plurality of traction plugs are attached to said finger elements for providing traction on the top surface of said finger element and the bottom surface of said finger element, each of said traction plugs having a flexible resilient top portion protruding above the top surface of said finger element and a flexible resilient base portion protruding below the bottom surface of said finger element; and

. attachment means for attaching said traction plugs to said finger elements with the plug top portion protruding above said finger element top surface and the base portion protruding below the bottom edge of said finger element side surfaces.

3. The modular floor mat of claim 1 including a plurality of traction ridges and grooves formed in the top surface of said tread surface generally adjacent each of said drainage openings to provide additional traction to said tread surface, said ridges positioned in alternating arrangement with said grooves and extending generally perpendicular to the peripheral sides of said drainage openings.

4. The modular floor mat of'claim 3-wherein said support flanges comprise a plurality of parallel spaced apart longitudinal support flanges integrally interconnected with a plurality of parallel spaced apart transverse support flanges, said longitudinal support flanges being generally perpendicular to said transverse support flanges, each of said flanges being generally thin and positioned generally perpendicular to the floor surface. i i I i S. The modular floor mat of claim 1 wherein said in terlocking means comprise a spherical interlock element protruding outwardly from one side of each of said finger elements and a spherical interlock detent formed in the opposite side of each of said finger elements, said interlock detent indexed with said interlock element for receiving the interlock element from the finger element of an adjoining mat module element therein to interlock adjoining floor mat modules when one finger element of a first floor mat module is forcibly inserted between adjoining finger elements of a second floor mat module.

6. The modular floor mat of claim 1 wherein said traction plug attachment means include a plurality of openings extending from the bottom edge of said support flanges through said tread surface, said openings being sized to receive said traction plugs therein with the top portion of said traction plug protruding above said tread surface and the bottom portion of said trac tion plug protruding below the bottom edge of said support flanges, said openings having an inside diameter smaller than the diameter of said traction plugs to forcibly retain said traction plugs when they are press-fitted into said openings.

7. The modular floor mat of claim ll including a plurality of spacing elements, each of said spacing elements positioned between adjacent finger elements and having a top surface which slopes downwardly and out wardly from said tread surface toward the floor surface terminating at a point along the side surface of said finger elements.

8. A unitary modular floor mat which can be used individually or in combination with other adjoining mat modules to cover a floor surface, comprising:

a. a unitary support frame comprised ofa plurality of parallel spaced apart longitudinal support flanges integrally interconnected with a plurality of parallel spaced apart transverse support flanges, said longitudinal support flanges being generally perpendicular to said transverse support flanges, each of said flanges being generally thin and positioned generally perpendicular to the floor surface, said support flanges having coplanar top and bottom edges;

b. a tread surface supported above the floor surface by said support frame, said tread surface having top and bottom surfaces, said bottom surface integrally attached to the top edges of said support flanges;

c. said tread surface containing a plurality of square drainage openings for draining substances off of the tread surface onto the underlying floor surface and ventilating the floor surface, said tread top surface containing a plurality of interconnected shallow drainage panels extending across the tread top surface and communicating with said drainage openings to drain liquids from said tread surface through said drainage openings;

d. a plurality of'tracti on ridges and grooves formed in the top surface of said tread surface generally adjacent each of said drainage openings to provide additional traction to said tread surface, said ridges positioned in alternating arrangement with said grooves and extending generally perpendicular to the peripheralsides of said drainage openings;

e. a plurality of finger elements protruding outwardly from each side of supportframe to intermesh with finger elements onan" adjoining mat module, each of said finger elements having at least two side surfaces which support a top surface, a first portion of said top surface being integral and coplanar with said tread top surface and a second portion being an inclined surface which. slopes outwardly and downwardly away from said tread surface toward the floor surface to form an inclined threshold sur rounding the mat periphery to prevent tripping;

f. each of said finger elements being spaced apart a sufficient distance so as to receive between adjacent finger elements a finger element from an adjoining floor mat module to create a generally continuous tread surface from interlocked mat modules;

g. interlock means attached to each of said finger element side surfaces to forcibly engage the finger element of an adjoining mat module which is positioned between adjacent finger elements, thereby interlocking adjacent floor mat modules, said interlock means including a spherical interlock element protruding outwardly from one side of each of said finger elements and a spherical interlock detent positioned in the opposite side of each of said finger elements, said interlock detent indexed with said interlock element for receiving the interlock element from the finger element of an adjoining mat module therein to interlock adjoining floor mat modules when their finger elements are interlaced;

h. a plurality of unitary traction plugs for providing traction to the top surfaces of said floor mat and the bottom surface of said support frame, each of said traction plugs having a flexible resilient top portion protruding above the top surfaces of said floor mat and a flexible resilient base portion protruding below the bottom edge of said support flanges to abut the floor surface;

i. attachment means for attaching said traction plugs to said floor mat with the plug top portion protruding above said tread surface and the top surface of said finger element and the plug base portion protruding below the bottom edge of said support flanges and said finger elements, said attachment means including a plurality of openings extending from the bottom edge of said support flanges through said tread surface, said openings being sized to receive said traction plugs therein with the top portion of said traction plug protruding above said tread surface on the bottom portion of said traction plug protruding below the bottom edge of said support flanges, said attachment means further including a plurality of openings extending through some of said finger elements, said openings being sized to receive said traction plugs therein with the top portion of said traction plug protruding above the top surface of said finger element and the bottom portion of said traction plug protruding below the bottom edge of said finger element, said openger elements comprise a first plurality of identical finger elements which have a generally trapezoidal planform with said side surfaces extending outwardly from said support frame and toward one another to form the trapezoidal planform, and a single finger element having a generally square planform and positioned at one comer of said floor mat, and a single finger element having a V-shaped planform and positioned at a corner of said floor mat diagonally opposite said generally square finger element. 

1. A unitary modular floor mat which can be used individually or in combination with other adjoining mat modules to cover a floor surface, comprising: a. a unitary support frame comprised of a plurality of interconnected and spaced apart support flanges, at least some of said support flanges having coplanar top and bottom edges; b. a tread surface supported above the floor surface by said support frame, said tread surface having top and bottom surfaces, said bottom surface integrally attached to the top edges of said support flanges; c. said tread surface containing a plurality of drainage openings for draining substances off of the tread surface onto the underlying floor surface and ventilating the floor surface; d. a plurality of finger elements protruding outwardly from each side of said support frame to intermesh with finger elements on an adjoining mat module, each of said finger elements having at least two side surfaces which support a top surface, a first portion of said top surface being integral and coplanar with said tread top surface and a second portion being an inclined surface which slopes outwardly and downwardly away from said tread surface toward the floor surface to form an inclined threshold surrounding the mat periphery to prevent tripping; e. each of said finger elements being spaced apart a sufficient distance so as to receive between adjacent finger elements a finger element from an adjoining floor mat module to create a generally continuous tread surface from interlocked mat modules; f. interlock means attached to each of said finger element side surfaces to forcibly engage the finger element of an adjoining mat module which is positioned between adjacent finger elements, thereby interlocking adjacent floor mat modules; g. a plurality of unitary traction plugs for providing traction to the tread surface and the bottom surface of said support frame, each of said traction plugs having a flexible resilient top portion protruding above the tread surface and a flexible resilient base portion protruding below the bottom edge of said support flanges to abut the floor surface; and h. attachment means for attaching said traction plugs to said floor mat with the plug top portion protruding above said tread surface and the plug base portion protruding below the bottom edge of said support flanges.
 2. The modular floor mat of claim 1 wherein: a. some of said plurality of traction plugs are attached to said finger elements for providing traction on the top surface of said finger element and the bottom surface of said finger element, each of said traction Plugs having a flexible resilient top portion protruding above the top surface of said finger element and a flexible resilient base portion protruding below the bottom surface of said finger element; and b. attachment means for attaching said traction plugs to said finger elements with the plug top portion protruding above said finger element top surface and the base portion protruding below the bottom edge of said finger element side surfaces.
 3. The modular floor mat of claim 1 including a plurality of traction ridges and grooves formed in the top surface of said tread surface generally adjacent each of said drainage openings to provide additional traction to said tread surface, said ridges positioned in alternating arrangement with said grooves and extending generally perpendicular to the peripheral sides of said drainage openings.
 4. The modular floor mat of claim 3 wherein said support flanges comprise a plurality of parallel spaced apart longitudinal support flanges integrally interconnected with a plurality of parallel spaced apart transverse support flanges, said longitudinal support flanges being generally perpendicular to said transverse support flanges, each of said flanges being generally thin and positioned generally perpendicular to the floor surface.
 5. The modular floor mat of claim 1 wherein said interlocking means comprise a spherical interlock element protruding outwardly from one side of each of said finger elements and a spherical interlock detent formed in the opposite side of each of said finger elements, said interlock detent indexed with said interlock element for receiving the interlock element from the finger element of an adjoining mat module element therein to interlock adjoining floor mat modules when one finger element of a first floor mat module is forcibly inserted between adjoining finger elements of a second floor mat module.
 6. The modular floor mat of claim 1 wherein said traction plug attachment means include a plurality of openings extending from the bottom edge of said support flanges through said tread surface, said openings being sized to receive said traction plugs therein with the top portion of said traction plug protruding above said tread surface and the bottom portion of said traction plug protruding below the bottom edge of said support flanges, said openings having an inside diameter smaller than the diameter of said traction plugs to forcibly retain said traction plugs when they are press-fitted into said openings.
 7. The modular floor mat of claim 1 including a plurality of spacing elements, each of said spacing elements positioned between adjacent finger elements and having a top surface which slopes downwardly and outwardly from said tread surface toward the floor surface terminating at a point along the side surface of said finger elements.
 8. A unitary modular floor mat which can be used individually or in combination with other adjoining mat modules to cover a floor surface, comprising: a. a unitary support frame comprised of a plurality of parallel spaced apart longitudinal support flanges integrally interconnected with a plurality of parallel spaced apart transverse support flanges, said longitudinal support flanges being generally perpendicular to said transverse support flanges, each of said flanges being generally thin and positioned generally perpendicular to the floor surface, said support flanges having coplanar top and bottom edges; b. a tread surface supported above the floor surface by said support frame, said tread surface having top and bottom surfaces, said bottom surface integrally attached to the top edges of said support flanges; c. said tread surface containing a plurality of square drainage openings for draining substances off of the tread surface onto the underlying floor surface and ventilating the floor surface, said tread top surface containing a plurality of interconnected shallow drainage panels extending across the tread top surface and communicating with Said drainage openings to drain liquids from said tread surface through said drainage openings; d. a plurality of traction ridges and grooves formed in the top surface of said tread surface generally adjacent each of said drainage openings to provide additional traction to said tread surface, said ridges positioned in alternating arrangement with said grooves and extending generally perpendicular to the peripheral sides of said drainage openings; e. a plurality of finger elements protruding outwardly from each side of support frame to intermesh with finger elements on an adjoining mat module, each of said finger elements having at least two side surfaces which support a top surface, a first portion of said top surface being integral and coplanar with said tread top surface and a second portion being an inclined surface which slopes outwardly and downwardly away from said tread surface toward the floor surface to form an inclined threshold surrounding the mat periphery to prevent tripping; f. each of said finger elements being spaced apart a sufficient distance so as to receive between adjacent finger elements a finger element from an adjoining floor mat module to create a generally continuous tread surface from interlocked mat modules; g. interlock means attached to each of said finger element side surfaces to forcibly engage the finger element of an adjoining mat module which is positioned between adjacent finger elements, thereby interlocking adjacent floor mat modules, said interlock means including a spherical interlock element protruding outwardly from one side of each of said finger elements and a spherical interlock detent positioned in the opposite side of each of said finger elements, said interlock detent indexed with said interlock element for receiving the interlock element from the finger element of an adjoining mat module therein to interlock adjoining floor mat modules when their finger elements are interlaced; h. a plurality of unitary traction plugs for providing traction to the top surfaces of said floor mat and the bottom surface of said support frame, each of said traction plugs having a flexible resilient top portion protruding above the top surfaces of said floor mat and a flexible resilient base portion protruding below the bottom edge of said support flanges to abut the floor surface; i. attachment means for attaching said traction plugs to said floor mat with the plug top portion protruding above said tread surface and the top surface of said finger element and the plug base portion protruding below the bottom edge of said support flanges and said finger elements, said attachment means including a plurality of openings extending from the bottom edge of said support flanges through said tread surface, said openings being sized to receive said traction plugs therein with the top portion of said traction plug protruding above said tread surface on the bottom portion of said traction plug protruding below the bottom edge of said support flanges, said attachment means further including a plurality of openings extending through some of said finger elements, said openings being sized to receive said traction plugs therein with the top portion of said traction plug protruding above the top surface of said finger element and the bottom portion of said traction plug protruding below the bottom edge of said finger element, said openings having an inside diameter smaller than the diameter of said traction plugs to forcibly retain said traction plugs when they are press-fitted into said openings; and j. a plurality of spacing elements, each of said spacing elements positioned between adjacent finger elements and having a top surface which slopes downwardly and outwardly from said tread toward the floor surface, terminating at a point along the side surface of said finger elements.
 9. The modular floor mat of claim 8 wherein said finger elements comprise a first plurality of identical finger elements which have a generally traPezoidal planform with said side surfaces extending outwardly from said support frame and toward one another to form the trapezoidal planform, and a single finger element having a generally square planform and positioned at one corner of said floor mat, and a single finger element having a V-shaped planform and positioned at a corner of said floor mat diagonally opposite said generally square finger element. 